Check out this video from Colorado pro trainer Ted Hoff at Cottonwood Ranch and Kennel that demonstrates gaining the attention of a dog that has received no training and doesn't understand the concept of being under control and executing commands to the fullest.
While it's incredible to watch Hoff bring the dog under control and gain the dog's fullest attention, the big part you should think about is why this is important.
Many of us amateur trainers go about our obedience training with lower standards than a pro trainer. If you watch the video, there are several of us that would accept that dog's first attempt at complying with the sit command. Listen to what Hoff says about it; about how the dog is sitting sloppy/sideways, shaking him off and doing it on his own terms.
If we, as amateurs, accept that behavior and don't follow through with making the dog comply fully, as Hoff demonstrates in a very positive, low-impact, way, sooner or later it's going to come back and bite us in the butt.
Maybe you don't see it right away, but it will manifest itself somewhere: slipping whistles, blowing you off in the field or during drills, losing control, unable to maintain control as distance increases or any number of other things.
Get it right, close, first, and make the dog do it properly, to your standards, not to what he deems proper, and you'll be on your way to more productive training sessions.
Watch the video and notice how the dog's body language, attention and positioning change from the beginning to the end of the video. He's sitting straighter, following in a proper heel position (with almost no compulsion imparted by Hoff) and his attention on the handler is more focused and lasts for longer durations.
Also pay attention to how hard Hoff is working; obedience training isn't a simple walk in the woods or around the block. It's changing direction, keeping the dog on his toes and asking him to comply and pay attention to you at all times; that requires you to think about what the dog is about to do and anticipate that action and respond accordingly.